High Functioning Autism vs. Low Functioning Autism: Is There a Difference?

When my son Lucas was young, I thought he had high functioning autism because he was included in typical toddler preschool classes and was warm and cuddly with me. But now most would consider Lucas low functioning. After two decades in the autism world, I really don’t like the terms “high functioning” and “low functioning”. So today I’m going to get on my soapbox about these terms, talk about how to tell, if it matters, and what to do about high functioning versus low functioning autism.

Each week I provide you with some of my ideas about turning autism around. So, if you haven’t subscribed to my YouTube channel, you can do that now. As I said, when Lucas was really young I didn’t think he had autism at all, and I was sure that if he was diagnosed with autism, it would be very mild autism. That kept me in denial for over a year, which was a very bad thing. I did a video blog on denial many months ago, so you may want to check that out now.

Even after Lucas was diagnosed with moderate to severe autism, I still considered him to be high functioning because he was going to typical preschool with a shadow and he wasn’t having many problem behaviors or self-stimulatory behaviors.

Then as Lucas got older, when he was about six or seven years old, I thought he was kind of in the middle of the spectrum but definitely not low functioning. That was until one day when I went to look at an approved private ABA school for Lucas. This is where I saw a little boy, I’ll call him “Nathan”. It was circle time at this ABA school and there was a boy sitting there. He flopped on the ground in the middle of story time and was throwing a tantrum. I wasn’t a Behavior Analyst at this point, so I just kind of looked on and thought about Lucas.

Lucas was used to going to typical preschool, he was enrolled in our public-school kindergarten program with a shadow and a special education teacher. He was still doing a home program for half the day, so in my mind, even though he had moderate to severe autism and wasn’t conversational, I thought Nathan was much lower functioning. At that point, I was thinking, “That’s it. Lucas does not belong here. I want him in typical, regular public school where he can get role modeling.” The director talked to me at the end of my short, one-hour visit, and she asked me if I thought this was a good fit for Lucas. I told her that I thought Lucas was higher functioning than the kids I saw there. She told me that Nathan, who had flopped to the ground during story time, was actually reading almost at grade level and had much more language than Lucas did.

The truth about the different levels of autism

At that point I had an aha moment, and I really realized that it wasn’t fair to call either child high functioning or low functioning because within each child are their strengths and their needs. Lucas blended into the community and public schools a lot better because he didn’t throw major tantrums or have problem behaviors to that extent. He had language needs, academic needs, and a bunch of other needs though.

But in terms of taking him out into the community, taking him to a restaurant, to a pool, or on an airplane, it made look Lucas look a little bit more higher functioning than other children who were more advanced in different areas. At this point I thought, “If you were a teacher, and you had six or eight kids with autism in your classroom, and you were told to line them up in terms of who’s the highest functioning and who’s lowest functioning, you would actually have a really hard time.” Are we talking about problem behaviors? Are we talking about going into the community? Are we talking about academics and language? There are a host of things that kids have issues with.

Some kids are more mild-mannered like Lucas, and blend in more while other kids have high problem behaviors. So within each child are their strengths and needs. At this point I realized it was impossible to really tell if a child had high functioning autism or low functioning autism, especially if they were younger. Over the years I’ve really realized that a lot of parents want to know that their 2-year-old or even say to others, “Oh, my 2-year-old just has high functioning autism,” or “You can’t tell how a two-year-old is going to be at 8 or 18.”

Want to get started on the right path and start making a difference for your child or client with autism?

The biggest thing I’ve learned over the years is you need to treat early autism like the worst case of autism you’ve ever seen in order to give your child or your client the best outcome possible. I did do another video blog a few months ago titled, “Can you predict how a 2-year-old’s going to be at age 8?” and you might want to check that out. Over the years this high functioning and low functioning thing has really been a blurry line for me, and when people say, “Oh, my son just has high functioning autism or just has Asperger’s,” I think that’s really a disservice to the child. I think for other moms whose kids are more impaired, it’s kind of like comparing cancer. You may have a better prognosis having thyroid cancer than pancreatic cancer, but cancer is still life altering, and you never know what is going to happen.

Low Functioning and High Functioning Autism Characteristics

I think the idea of high functioning and low functioning gets even more complicated. In general, when people say kids have high functioning autism, they tend to mean that the child has full language and are conversational. Many times, these high functioning kids can be included in general education settings and may be high enough functioning to learn how to drive, go to college, and perhaps get married. But with high functioning autism also comes some co-morbid conditions like anxiety at a higher rate, depression, and those sorts of things. It comes with additional stress at many times.

When many people use the term low functioning, they use it to think of kids that also have an intellectual disability in addition to their autism. They might have little to no communication or language and they’re less likely to be fully included. Now the DSM-5, which gives a diagnosis criterion for autism, has three levels of ASD. Level 1 is more mild autism, higher functioning, and Level 3 would be kids like Lucas who need very substantial support. Over time these levels could change. You could start out as a Level 3, and with the right therapy, you could move into Level 1; I’ve seen this many time with my own eyes.

Obviously, there’s a whole spectrum in between going to college, driving a car, and being completely in need of constant support and supervision. Some high-functioning kids are fully conversational, but they can’t hold a job due to that anxiety or depression, while there’s some low-functioning kids who grow up and are gainfully employed and happy, living with only some minor support. In the end, it doesn’t matter if you call someone “high functioning” or “low functioning”, it’s about each child or adult with autism reaching their fullest potential, using their strengths to bring up their weaknesses, improving those deficits, and helping each child be as safe, as independent, and as happy as possible.

When kids are really young, maybe not diagnosed with autism or newly diagnosed, it’s impossible to tell how they are going to do long term. So, as I said earlier, it’s best to treat autism aggressively even if you think it’s very mild. Wherever you’re watching this video blog, I would love it if you would leave me a comment, give me a thumbs up, and share this video with others who might benefit.

To learn more about how to help children with autism, you can sign up for one of my free online workshops today that will help you increase language and decrease problem behaviors in your child or client with autism. I’ll see you right here next week.

Want to get started on the right path and start making a difference for your child or client with autism?